Breaking Down the Chiefs Defense

Independent analyst Andrew Mason examines a Chiefs defense that has allowed the fewest points per game in the NFL.

ENGLEWOOD, Colo. -- Tamba Hali and Justin Houston are just the starting point of Kansas City's defense.

Their ability to line up wide and quickly sprint outside opposing offensive tackles has helped push them to 20 sacks combined so far this season. But as outside linebackers, their duties are versatile; they are adept enough in coverage to where you can't see them drop back and think you have an opening, and any mistakes they might make in defending the run largely don't matter, because the Chiefs' primary defensive line of Mike Devito, Tyson Jackson and nose tackle Dontari Poe is arguably the league's best.

Poe, in particular, has taken the second-year leap that teams hope to see from interior defensive linemen selected in the early rounds. His quickness off the snap has helped him to five sacks, the most by any 3-4 nose tackle in the league this year.

"I think he's done exactly what I thought he would do," said Interim Head Coach/Defensive Coordinator Jack Del Rio. "There were a lot of differing opinions of him coming out (of the University of Memphis), but that was an easy one to grade, in my opinion. Big, strong, talented guy. He's got all the ability in the world. I didn't have any doubt he'd be a good player in this league."

One play where Poe's ability to alter the pass rush was on the Chiefs' first sack of Houston quarterback Case Keenum, in Week 7. After going the entire first half without bringing down the first-time starter, Derrick Johnson got to Keenum to force a punt on the first series after halftime, capitalizing off Poe, who forced three blockers to engage with him as he moved from right to left across the line. Johnson had been waiting behind Poe; when Poe cut across, Johnson came behind him, and took advantage of an off-balance Wade Smith, who was playing on his heels after Poe's rush. Johnson bounced off Smith and easily got the sack.

Poe also helps the Chiefs disguise their intentions, which they prominently displayed in a 17-16 win over Houston in Week 7. On the afore-mentioned sack by Johnson, safety Eric Berry crept close to the line, and then backed off. With Poe occupying attention, Brandon Flowers, working the slot cornerback position, accelerated in for a supplemental rush.

Flowers got a sack one quarter later while blitzing from slot corner, which again showed disguised intentions. Houston lined up inside at the line of scrimmage in a stand-up position over Smith, who was working at left guard. As Houston dropped back in the right side of the defense, the Chiefs overloaded the left side, with Poe working inside, Hali coming from the outside, and Johnson stunting inside Poe to force the right guard to engage. Flowers then sprints into the backfield, unblocked, and gets the sack.

Whether the Chiefs can repeat this depends largely on Peyton Manning's well-renowned ability to diagnose a defense's intentions, and that's what makes this matchup arguably the most anticipated of the season to date. There is a connection between sacks and the experience of opposing quarterbacks; 20 of the Chiefs' 36 sacks came against the four quarterbacks they have faced who came into this season with 700 or fewer career passes: Keenum, Jeff Tuel, Blaine Gabbert and Terrelle Pryor. Against these quarterbacks, the Chiefs got one sack every 7.65 pass plays; against everyone else, the rate is one sack every 13 pass plays (which is still slightly better than average; the league-wide rate is one every 14.46 pass plays).

And it also must be noted that the sack tap has been turned down recently. Kansas City has just one sack in its last two games and six in its last three after racking up 30 in the first six games, peaking with nine sacks against Oakland in Week 6.

There are reasons. Opponents have adapted, putting more resources into protection. And arguably the two best offensive lines the Chiefs have faced have been the last two: Cleveland's is anchored by Pro Bowl left tackle Joe Thomas, who has only allowed one sack all year and limited Hali to just one pressure.

Buffalo, the team Kansas City defeated in Week 9 to move to 9-0, is bolstered by a blocking scheme has allowed them to permit one hurry every 4.66 pass plays, according to ProFootballFocus.com's metrics; this is sixth-best in the league. Their work up front has allowed the Bills' inexperienced collection of quarterbacks to stay upright, and kept Kansas City's pass rush from being much of a factor in that game, forcing the Chiefs to rely on their coverage and the potential for forced throws by a rookie quarterback.

And whose hurry rate is the best among the offensive line? Appropriately, it's the team of "hurry, hurry," the Broncos, who have permitted one quarterback hurry every 6.46 pass plays.

Their rate of quarterback hits allowed is also the league's best -- one every 12.83 pass plays -- and the sack rate of one every 29.62 pass plays is best in the AFC, and only trails Detroit league-wide.

"It's a little bit to do with the (offensive) line, a little bit to do with the fact that our quarterback gets rid of the ball fairly quickly," said Offensive Coordinator Adam Gase, "but we have to get better as a group. If everyone does their job the right way, we'll get better in that area."

In that case, the Broncos would not only get better -- they'd be likely to knock the Chiefs off their unbeaten perch.

ALSO OF NOTE:

* Health has been a crucial aspect of the Chiefs' success this year. The Chiefs have used just 66 defensive personnel groupings so far this season, by far the least in the league. No one else has used less than 108. The average team has used 165 different groupings. Denver is at the opposite end of the spectrum; its 280 groupings leads the league -- an average of 31.1 different personnel groupings per game. Kansas City uses 7.33 per game.

* Kansas City has permitted a league-worst 5.0 rushing yards per carry this year. But the Chiefs rank 15th in first-down percentage allowed, with the chains moving on 21 percent of the carries against them. Perhaps most troublesome for Kansas City is the average per rush on first-and-10 situations: 5.06 yards. The Broncos, by comparison, are 27.3 percent better, allowing 3.68 yards per first-and-10 run.